Isoflavones Contents and Physiological Activities of Soybeans Fermented with Aspergillus oryzae or Bacillus natto

• Published in: Han'guk Sikp'um Yŏngyang Kwahakhoe chi Vol. 37; no. 2
• Main Authors: Chung, W.Y. (Hankyong National University, Ansung, Republic of Korea), Kim, S.K. (Northern Branch of Gyeonggido Agricultural Research and Extension Services, Yeoncheon, Republic of Korea), Son, J.Y. (Hankyong National University, Ansung, Republic of Korea), E-mail: nawin98@chol.com
• Format: Journal Article
• Language: Korean
• Published: 01.02.2008
• Subjects: fermented soybeans; FLAVONOIDE; FLAVONOIDES; FLAVONOIDS; isoflavone content; physiological activities
• ISSN: 1226-3311
• DOI: 10.3746/jkfn.2008.37.2.141

This study investigated the isoflavone contents and physiological properties of non-fermented soybean (NF) and the fermented soybeans prepared with Asp. oryzae (AO) and B. natto (BN). The total isoflavone contents (daidzin, genistin, daidzein and genistein) of NF, AO and BN were 81.8 mg/100 g, 130.7 mg/100 g and 139.5 mg/100 g, respectively. Especially, the total phenol contents of NF, AO and BN were 2.1%, 4.3% and 7.6%, and the total flavonoid contents were 1.3%, 1.6% and 2.7%, respectively. The nitrite-scavenging abilities of NF, AO and BN were 34.4%, 55.2% and 92.5%, respectively. Antimicrobial activity of BN was shown to be the strongest to Bacillus cereus, Staphylococcus aureus and Escherichia coli. The SOD-like activity was the strongest in AO, whereas the electron donating ability was the strongest in BN. Antioxidant activity of AO at concentration of 0.02% was stronger than BN or NF.